Abstract: I will give an overview of automated image retrieval techniques that utilise the content of the image as opposed to metadata.

The common best practice of locating images in most commercial image databases is still a structured text search in metadata and in free text describing the images. Generating the right metadata and image description is a process that is subjective, costly, and depends on language, ontologies, (controlled) vocabulary and, ultimately, the purpose of the search.

Utilising the image content itself and an automated analysis of the images holds the promise of improving and widening access to image databases, but indexing image content is made difficult by a number of challenges: some aspects of external metadata simply cannot be extracted by analysing the image contents; there is a pronounced semantic gap between human interpretation and low-level image features; image elements have many meanings and interpretations, which forms yet another barrier to automated image understanding.

I will argue that — in particular in vertical domains of image search — some of these challenges can be tackled by automated processing, machine learning and by utilising the skills of the user, for example through browsing or through a process that is called relevance feedback, thus putting the user at centre stage.Short bio. Stefan

He carved out his academic career at Imperial College London (1997--2006), where he also held an EPSRC Advanced Research Fellowship (1999-2004). In

2006 he became a Professor of Knowledge Media when he joined The Open University's Knowledge Media Institute to cover the area of Multimedia and Information Systems. He currently holds a Honorary Professorship from the University of Waikato, New Zealand, and a Visiting Fellowship at Cranfield University.

Stefan has published widely in the area of Multimedia Information Retrieval. Amongst other projects, he was Principal Investigator in the EPSRC-funded Multimedia Knowledge Management Network, of an EPSRC grant to research and develop video digital libraries and for The Open University in the European FP6-ICT project PHAROS that established a horizontal layer of technologies for large-scale audio-visual search engines. Stefan has given lectures at summer schools, e.g., ESSIR (2009 and 2011) and RuSSIR (2010 and 2011), as well as tutorials at key conferences. He is currently programme co-chair of ECIR 2013 and of WI 2013, has been posters chair of IiiX 2012, programme co-chair of SAMT 2010, programme co-chair of WI 2010, programme chair of IRFC 2010, general chair of ECIR 2010, general co-chair of ICTIR 2009, and general chair of ECIR 2006. As of 2012, he has served the academic community through being a journal editor (4x), guest editor (4x), as referee for a wide range of Computing journals (32), international conferences (65) and for research sponsors (14), in particular, EPSRC, the European Commission and the European Research Council. Stefan is a member of the EPSRC College; ACM; BCS; and a fellow of the Higher Education Academy.